CN2777522Y

CN2777522Y - Double plate self-compensation strain sensor

Info

Publication number: CN2777522Y
Application number: CN 200520022877
Authority: CN
Inventors: 王乐善
Original assignee: No702 Inst Of No1 Academy Of China Astronautical Science And Technology Group
Current assignee: No702 Inst Of No1 Academy Of China Astronautical Science And Technology Group
Priority date: 2005-03-22
Filing date: 2005-03-22
Publication date: 2006-05-03
Anticipated expiration: 2015-03-22

Abstract

The utility model relates to a double plate self-compensation strain sensor. Two high-temperature strain pieces which have the same performance are fixed on one or two small structural pieces which has the same material with the high-temperature strain pieces to form a fixed structure; the other side of the small structural pieces corresponding to one strain piece is fixed on a bottom support to form the fixed structure; besides, the other side of the small structural pieces corresponding the other strain piece is fixed together with the bottom support through a strain isolating pad. The bottom support and the small structural pieces can use metal plates, such as aluminum alloy pieces and steel pieces, and non-metal plates, such as paper pieces, plastic pieces, etc. can be also used; the thickness of the metal or the non-metal plates is between 0.1 millimeters and 0.3 millimeters; the fixed structures are adhesive joint structures or welded structures which use high-temperature strain adhesives. The utility model has the advantages of simple structure and simple manufacture, and the application of the utility model can further eliminate visual strain of an experimental structural body under the action of high temperature and external load and raise the measuring precision.

Description

A kind of biplate system self-compensating strain transducer

Technical field

The utility model relates to a kind of biplate system self-compensating strain transducer.

Background technology

For many years, strain ga(u)ge is the conventional means of strain under the measurement structure normal temperature, stress.Foil gauge is the main element in the strainometer, when strain under the measurement structure normal temperature, stress, bonding or be welded on test structure body examination point place foil gauge, after measured structure is stressed, the strain at structure measuring point place is done representative with being bonded in the strain of foil gauge herein, with electric signal output, the relation value curve by strain one electric signal that calibrates in advance can calculate strain, stress.At present, measure strain, the stress of structure under the high temperature and also continue to use the method, adopts methods such as bonding or welding, the high temperature resistance foil gauge is fixed on structure measuring point place, be used for high-temp strain, the stress of measurement structure body under heating and loading environment.High temperature strain foil generally all is to work in the self compensation mode, in order to reduce or eliminate owing to wire grid temperature-coefficient of electrical resistance α _R, linear expansion coefficient (wire grid β _GWith structure base material β _S) the non-strain signal ε (T) of inharmonious initiation.Under uniform temperature, ε (T)=α _R* T/K+ (β _G-β _S) * T, wherein T represents temperature, K represents tension gauge factor.Striving making ε (T) is zero to be the self-compensating target of high temperature strain foil.But existing high temperature strain foil self compensation is insufficient, and ε (T) is not equal to zero, also has the bigger non-strain signal that is commonly called as apparent strain ε (T) under different temperatures.In actual measurement, for reducing error, on the self compensation basis of foil gauge, increase an apparent strain correction again, its practice is, in giving examination, measures to be bonded at the desire test and tests the described apparent strain ε (T) of compensating plate under different temperatures in the test piece of structure homogeneity; In the structural test at high temperature, when measuring this high-temp strain, measure this dot structure temperature T, during the data processing of test back, in the high-temp strain signal U that measures, deduct the apparent strain ε (T) under this T temperature, be high-temp strain ε=U-ε (T).

Practice for many years shows, no matter is to glued joint the foil gauge structure, or the weld strain chip architecture, and when measuring high-temp strain, the high-temp strain of measuring all has than mistake, and high temperature strain measurement credible result degree is under suspicion.Its reason is a lot of, and the foil gauge that the first is bonding, bonded adhesives are in solidification process, and the apparent strain signal constantly changes, and test does not first repeat with test several times thereafter, so the correction of above-mentioned strain signal U is wrong; It two is that adhesives causes between test structure body and the wire grid thermal resistance is arranged, and thermal resistance constantly changes in the whole process of heating, cause the foil gauge wire grid different with test structure body examination point temperature, under the condition of Fast Heating, because thermal resistance, foil gauge wire grid and test structure body examination point exist the temperature difference, and this kind temperature difference also causes apparent strain ε (T ₁), so the correction of above-mentioned strain signal U is also wrong.

The utility model content

The purpose of this utility model is to improve the shortcoming of prior art and the biplate system that a kind of apparent strain is little, measuring accuracy is high self-compensating strain transducer is provided.

For achieving the above object, the utility model is taked following design proposal: it is that two high temperature strain foils of same performance are separately fixed on the identical structure small pieces of two materials, constitutes fixed sturcture; The opposite side of the structure small pieces of a corresponding foil gauge is fixed on the collet, also constitutes fixed sturcture; And the opposite side of the structure small pieces of corresponding another foil gauge is fixed by strain isolating pad and described collet.Described structure small pieces adopt metal sheet, as aluminum alloy sheet, steel disc etc.; Described collet can adopt metal sheet, as aluminum alloy sheet, steel disc etc., also can adopt non-metallic sheet, as the scraps of paper, plastic sheet etc.Described metal or non-metallic sheet thickness are the 0.1-0.3 millimeter.Described fixed sturcture is bonded structure or the welded structure that adopts high-temp strain glue.Described collet sheets of sizes is greater than the foil gauge size, in case of necessity the edge bendable of collet fold to foil gauge the top with shielded strain gauge, prevent heat radiation.

The utility model principle of work is: biplate system self-compensating strain transducer is bonding or be welded on the test structure body by collet, the heating on request of test structure body, the loading procedure heating, load, because of described this biplate is under the same thermal environment from two foil gauges mending on the compensate for strain sensor, the test structure body is under high temperature and external load function, the gluing foil gauge that connects of high-temp strain on the structure small pieces will produce the strain variation that comprises apparent strain with the distortion of test structure body, change and only produce the apparent strain that causes by high temperature with another foil gauge that the strain isolating pad is isolated, the strain variation that is caused by external applied load on the test structure body passes less than on this sheet foil gauge because of isolating with the strain isolating pad, when test, two foil gauges are connected on respectively on two adjacent arms of test bridge circuit, utilize the bridge circuit complementary principle, two the apparent strain that same apparent strain is arranged that is under the same thermal environment is cancelled out each other, measure the strain differential that is attached to two of same measuring points, just measure the strain under the measuring point place high temperature and external load function on the test structure body.

The utility model is simple in structure, is easy to make, and the apparent strain of test structure body under high temperature and external applied load acting in conjunction can be further eliminated in its application, improves measuring accuracy.

Description of drawings

Fig. 1 the utility model structural representation

Embodiment

As shown in Figure 1 and Figure 2, the utility model is that two high temperature strain foils, 1, the 2 usefulness high-temp strain glue 3 of same performance are separately fixed on the two chip architecture small pieces 4,5, constitutes fixed sturcture; The opposite side of the structure small pieces 4 of corresponding foil gauge 1 is fixed on the collet 6 with high-temp strain glue 3, constitutes fixed sturcture; The opposite side of the structure small pieces 5 of another foil gauge 2 is fixed by strain isolating pad 7 and described collet 6.Described collet 6 and structure small pieces 4,5 adopt the metal steel disc, and this steel plate thickness is 0.1 millimeter.Described collet 6 sheets of sizes are greater than

foil gauge

1,2 sizes.

Claims

1, a kind of biplate system self-compensating strain transducer is characterized in that: it is that two high temperature strain foils of same performance are fixed on the identical structure small pieces of two materials, constitutes fixed sturcture; The opposite side of the structure small pieces of a corresponding foil gauge is fixed on the collet, also constitutes fixed sturcture; And the opposite side of the structure small pieces of corresponding another foil gauge is fixed by strain isolating pad and described collet.

2, a kind of biplate system self-compensating strain transducer according to claim 1 is characterized in that: described structure small pieces adopt metal sheet, as aluminium flake, steel disc.

3, a kind of biplate system self-compensating strain transducer according to claim 1 is characterized in that: described collet adopts metal sheet, as aluminium flake, steel disc, also can adopt non-metallic sheet, as the scraps of paper, plastic sheet.

4, a kind of biplate system self-compensating strain transducer according to claim 1 and 2, it is characterized in that: described metal or non-metallic sheet thickness are the 0.1-0.3 millimeter.

5, a kind of biplate system self-compensating strain transducer according to claim 1 is characterized in that: described fixed sturcture is the bonded structure that adopts high-temp strain glue.

6, a kind of biplate system self-compensating strain transducer according to claim 1, it is characterized in that: described fixed sturcture is a welded structure.